In order to make it easier to understand how we can integrate a robotic arm with MoveIt!, we have provided a set of packages containing all of the necessary configurations, robot descriptions, launch scripts, and modules to integrate MoveIt! with ROS, Gazebo, and RViz. We will not cover the details of how to integrate a robot with Gazebo as that has been covered in other chapters, but an explanation on how to integrate MoveIt! with Gazebo will be provided. The following packages are provided in the repository for this chapter, in the chapter7_tutorials directory:

• chapter7_tutorials: This repository acts as a container for the rest of the packages that will be used in this chapter. This sort of structure usually requires a metapackage to let catkin know that the packages are loosely related; hence, this package is the metapackage of the repository.
• rosbook_arm_bringup: This package centralizes the launching of the controllers and MoveIt!. It brings up the robot-either the real one or in simulation.
• rosbook_arm_controller_configuration: This package contains the launch files to load the controllers required to move the arm. These are trajectory (JointTrajectoryController) controllers used to support the MoveIt! motion planning.
• rosbook_arm_controller_configuration_gazebo: This package contains the configuration for the joint trajectory controllers. This configuration also includes the PID values required to control the arm in Gazebo.
• rosbook_arm_description: This package contains all of the required elements to describe the robotic arm, including URDF files (actually Xacro), meshes, and configuration files.
• rosbook_arm_gazebo: This package is one of the most important packages, containing the launch files for Gazebo (which will take care of launching the simulation environment as well as MoveIt!) and the controllers, as well as taking care of running the launch files required (mainly calling the launch file in rosbook_arm_bringup but also all the previous packages). It also contains the world's descriptions in order to include objects to interact with.
• rosbook_arm_hardware_gazebo: This package uses the ROS Control plugin used to simulate the joints in Gazebo. This package uses the robot description to register the different joints and actuators, in order to be able to control their position. This package is completely independent of MoveIt!, but it is required for the integration with Gazebo.
• rosbook_arm_moveit_config: This package is generated through the MoveIt! Setup Assistant. This contains most of the launch files required for both MoveIt! and the RViz plugins as well as several configuration files for MoveIt!.
• rosbook_arm_snippets: Except for the pick and place example, this package contains all of the snippets used throughout the chapter.
• rosbook_arm_pick_and_place: This package is the biggest and most complex example in the section, containing a demonstration of how you can perform object picking and placing with MoveIt!.